1. Field of the Invention
The present invention relates to an inkjet head comprising nozzles that discharge ink.
2. Description of the Related Art
An inkjet head distributes ink supplied from an ink tank to a plurality of pressure chambers. Ink that is distributed to the pressure chambers is pressurized by actuators and discharged from nozzles communicating with these pressure chambers. Piezoelectric elements including piezoelectric ceramic may be employed as the actuators. Japanese Patent Application Laid-open No. 2003-341056 (FIG. 3, paragraph number 0066; hereinafter referred to as “Patent Document 1”) discloses a technique wherein, in an inkjet head employing piezoelectric elements as actuators, the side face of a piezoelectric element is covered by adhesive that is used to stick together the piezoelectric element and a channel-forming substrate in which pressure chambers are formed. With the technique disclosed in Patent Document 1, damage to the piezoelectric elements caused by the external environment can be easily and reliably prevented.
Also, Japanese Patent Application Laid-open No. 2004-160967 (FIG. 11; hereinafter referred to in “Patent Document 2”) discloses an inkjet head in which a plurality of actuator units respectively provided with a large number of actuators are stuck onto a channel unit comprising a large number of nozzles and a large number of pressure chambers. Such actuator units comprise a piezoelectric sheet spanning a large number of pressure chambers, a large number of individual electrodes arranged to positionally correspond to pressure chambers respectively, and common electrodes sandwiching the piezoelectric sheet together with the large number of individual electrodes. The individual electrodes can be arranged with high density by employing an actuator unit as in Patent Document 2.